PROJECT SUMMARY/ABSTRACT Over half of low income children in the U.S. have experienced tooth decay, one-third of whom have untreated decay. Tooth decay in children is largely preventable with routine dental care that includes professionally applied topical fluoride and dental sealants. However, low income children who are at the greatest risk of developing tooth decay are the least likely to receive these services ? even if they do see a dentist for routine care. A large body of previous research has examined barriers to dental care and factors associated with preventive dental utilization from the patient perspective; limited research has focused on how dentist treatment patterns contribute to disparities. In this study, we will evaluate how regional patterns in clinical dental practice affect dentists' rates of providing preventive dental services to children who are at elevated risk for tooth decay. The outcome of interest is the proportion of children treated by each dentist who received preventive dental services, including rates of topical fluoride and dental sealant placement. Dentists' service patterns will be explored in the context of dental service areas ? regional markets identified based on where patients travel to receive care. Variation in rates of preventive dental services will be examined at the individual dentist level, and variation within and among service areas will be estimated. The project aims are to: (1) assess provider-level variation in the provision of preventive dental services, (2) evaluate clinical practice variation within and across geographical regions, and (3) identify factors associated with increased preventive dental service rates. Our long-term goal is to explore the mechanisms by which local clinical treatment patterns develop in order to identify modifiable factors that can be leveraged by educational interventions to increase use of science-based information by dentists. The long- term impact of these interventions would be to increase use of preventive dental services and reduce oral health disparities in high risk populations. This proposed project addresses NIDCR's 2014-2019 Strategic Plan goal to overcome disparities in dental, oral, and craniofacial health. It also addresses Healthy People 2020 Oral Health Objectives 8, 12, and 14, which aim to increase the proportion of children and adolescents who receive preventive dental services. Dentists' propensity to provide evidence-based preventive dental services is potentially modifiable; findings from this study will support design of tailored educational interventions and policy. Targeting behavior change at the provider level could offer a cost-effective method to reduce oral health disparities in children by shifting treatment patterns towards prevention.